Message type: E = Error
Message class:  SD_FREE_GOODS_MSG - Message class for Free Goods maintenance 
Message number: 026
Message text: Additional quantity is required.
Since SAP believes that this specific error message is 'self-explanatory,' no more information has been given.The majority of messages in the SAP system have a message text, however this is frequently insufficient to comprehend or resolve the problem.
To make things easier, more detailed information is frequently added to describe the issue, how to fix it, and the necessary steps or configuration modifications.
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The SAP error message SD_FREE_GOODS_MSG026 ("Additional quantity is required") typically occurs in the context of free goods processing in the Sales and Distribution (SD) module. This message indicates that the system expects a certain quantity of goods to be included in the sales order to qualify for free goods, but the required quantity has not been met.
Cause:
Free Goods Configuration: The free goods determination might be set up in such a way that a minimum quantity of the main product must be ordered to qualify for free goods.
Sales Order Quantity: The quantity entered in the sales order for the main product is less than the minimum required to trigger the free goods.
Promotion or Pricing Condition: There may be specific conditions or promotions that require a certain quantity to be eligible for free goods, and these conditions are not being met.
Solution:
Check Free Goods Configuration:
Go to the configuration settings for free goods in Get instant SAP help. Sign up for our Free Essentials Plan.
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SD_FREE_GOODS_MSG025 Unit for minimum quantity and free goods quantity is required.
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SD_FREE_GOODS_MSG027 Unit for additional quantity is required.
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SD_FREE_GOODS_MSG028 Additional material for free goods is required.
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